5u^2-90=0

Solution for 5u^2-90=0 equation:

Simplifying
5u2 + -90 = 0

Reorder the terms:
-90 + 5u2 = 0

Solving
-90 + 5u2 = 0

Solving for variable 'u'.

Move all terms containing u to the left, all other terms to the right.

Add '90' to each side of the equation.
-90 + 90 + 5u2 = 0 + 90

Combine like terms: -90 + 90 = 0
0 + 5u2 = 0 + 90
5u2 = 0 + 90

Combine like terms: 0 + 90 = 90
5u2 = 90

Divide each side by '5'.
u2 = 18

Simplifying
u2 = 18

Take the square root of each side:
u = {-4.242640687, 4.242640687}